to ruin so soon as justice departs from it, i.e., so soon as its inferior principles prevail over its superior ones, so soon as what was meant to obey presumes to take the office of governor.
49. The philosophical school founded by Plato is known in the history of philosophy as the Academy, so called from the groves of Academus where Plato was in the habit of addressing his disciples. The Academy is usually divided into three, the old, the middle, and new. The latter two may occupy our attention for a brief period hereafter: meanwhile I speak merely of the old Academy, which embraced and was presided over by the immediate followers of Plato. None of the writings of these older Platonists have come down to us. All that is known of their opinions is gathered from a few brief and incidental notices which occur in certain ancient authors. We are not, therefore, in a position to speak with any certainty of the manner in which they may have modified or carried forward the philosophy of their master. I shall merely make mention of Plato's three more immediate followers, Speusippus, Xenocrates, and Polemon, who succeeded him as the heads of the Academy.
50. Speusippus was the nephew of Plato. He was born probably about 400 B.C.—a calculation which makes him about thirty years younger than his
